Musical vibration translating unit



Feb. 22, 1949.

B. MINSHALL MUSICAL VIBRATION TRANSLA'IING UNIT Filed May 22, 1945Patented Feb. 22, 1949 UNITED STATES i- ATENT OFFICE MUSICAL VIBRATIONTRANSLATING UNIT Burton Minshali, Brattleboro, Vt. Application May 22,1945, Serial No. 595,239

(01. fi l-1.14)

12 Claims. 1

This invention relates to a unit for translating the vibrations ofreeds, such as are used in the ordinary reed organ as a source of tone,into electrical oscillations and more especially to an improvedarrangement in which each vibratory reed is positioned to vibrate withinthe electrostatic field of an electrical capacity formed by stationaryelectrodes. The condenser formed by these electrodes is connected to anelectrical circuit through which the electrical capacity is charged,

but the vibratory reed is not conductively coupled to this chargingmeans.

Hitherto, the musical vibrations of reeds have been translated intoelectrical oscillations by employing the reed as one plate of thecondenser in the manner disclosed in Patent 2,015,014. to Fredreck A.Hoschke. In this arrangement the metallic reed is conventionally housedor mounted in a Wooden cell and the reed, or a resilient metal stripattached to the base of the reed, is secured to a connection to theelectrical circuit in order that it may form one plate of the condenser.This construction is impractical because of the necessity of removingthe reed for tuning and servicing.

Moreover, the reed or the metal strip over a period of time becomescorroded, due to atmospheric action. This deterioration results in thecreation of a varying resistance at the point of connection with theelectrical circuit, thereby causing disturbances which are reproduced asnoise through the amplifier. In addition, the wooden cell in which thereed is mounted has a tendency to absorb moisture, and such conditionswill cause a leakage of the voltage carried by the reed, both to theground and to the remaining plate of the condenser. If leakage occurs anunsatisfactory performance of the musical instrument will necessarily bethe result. Furthermore, metal filings resulting from tuning the reed,may attach themselves to the stationary plate and to the reed and resultin shorting the circuit to the energizing voltage, thereby causing theinstrument to be wholly inoperative.

One of the objects of this invention is to overcome the above mentioneddisadvantages of the prior art.

Another object of this invention is to provide a unit, for translatingthe vibrations of a tone reed into electrical oscillations, which willoperate efliciently and assist in accurate reproduction under alloperating conditions.

A further object of my invention is to provide a unit for translatingthe vibrations of a tone reed into electrical oscillations in which thereed is positioned to vibrate within the electrostatic field of anelectrical capacity formed by station-- ary electrodes.

With these and other objects in view which may be instant to myimprovements, the invention consists in the parts and combinationshereinafter set forth in the claims, with the understanding that thenecessary elements comprising the invention and the arrangement of theseparts may be varied by those skilled in the art without departing fromthe spirit of the invention or the scope of the appended claims.

The invention embraces broadly the idea of providing a musicalinstrument employing reeds, of the type used in the ordinary reed organas its source of tone, with a means for translating the vibrations ofthe reeds into electrical oscillations. Subsequently these oscillationsare amplified and reproduced as sound waves. In this arrangementstationary electrodes mutually forming an electrical capacity areprovided for each reed. These condensers are connected to a source ofelectrical potential for charging their capacities. In this invention, areed made of any suitable material, such as a metallic or plastic reedmay be employed. In musical instruments such as organs, the reeds arechromatically arranged in a musical scale.

The principal feature of the invention resides in positioning the reedto vibrate within the electrostatic field of the condenser so as toinfluence the capacity of the condenser without requiring the reed to beconnected to the electric circuit or to the ground. Suitable means, suchas pneumatic means, are provided to vibrate the reeds.

This construction eliminates the previously discussed disadvantages ofthe prior art and will provide eflicient operation and accuratereproduction over substantial periods of time.

In order to make my invention more clearly understood, reference is madeto the accompanying drawings which are for the purpose of illustratingpreferred arrangements for carrying the invention into practical efiect.

In the drawings:

Figure 1 discloses a longitudinal sectional view of a reed cell and anarrangement designed to form a vibration translation unit embodying thepresent invention.

Figure 2 discloses a modification, of the arrangement shown in Figure l,in which a plate is used as one of the electrodes of the condenser.

Figure 3 is a cross sectional view of a cell in which the reed ispositioned between spaced electrodes.

Figure 4 discloses a modification, of the arrangement shown in Figures 1and 2, in which the electrodes forming the condenser consist of a sleeveand a screw concentrically mounted therein.

In the four forms of the invention shown in the drawings for purposes ofillustration, a conventional reed cell I is disclosed in which a valveor pallet controls the passage of air under pressure through a duct 2 inthe block 3 to a metallic reed d. The reed is secured at one end to aframe 5 which in turn is attached to the duct block 3. Secured above threed in spaced relationship thereto such as by brackets 6, is aninsulating strip '5' in which are mounted a pair of spaced electrodes 8and 9 forming a condenser l0.

These electrodes are shown connected to a conventional charging andamplifying circuit through which electrical oscillations may betransmitted and amplified. The electrical capacity of the condenser Illis charged through the lead H which connects a source of electricity tothe electrode 8. The remaining electrode 9 is connected by a wire 12 t0the grid element of the input amplifier H3.

The reed 4 is positioned to Vibrate within the electrostatic field ofthe condenser it. This motion disturbs the field and therefore thecapacity of the condenser and, as a result the vibrations are impressedupon the amplifying circuit in the form of electric oscillations whichare then amplified and reproduced as sound waves. An axial ad justmentof the electrodes with respect to the reed will directly effect thedegree of this disturbance.

In the form of the invention shown in Figure l, the free end of the reed4 is positioned directly beneath the electrodes 8 and 9 forming thecondenser iii. These electrodes are formed by a pair of screws, both ofwhich are adjustable axially with respect to the reed 4. This simplifiedstructure forms a very effective unit embodying the present invention.

In the modification shown in Figure 2, the electrode of the condenseri9, which is attached to the source of electricity, is a plate 3A whichis preferably formed from a piece of foil which may be attached to thestrip 7 by a suitable ad hesive. This is a less expensive constructionand is effective because the adjustment of the screw forming theelectrode 8 is sufiicient to effect the relationship between thecondenser l0 and the reed 4.

In the modification of the invention shown in Figure 3, the electrodes 8and 9 of the condenser i8 consist of a pair of screws such as are alsoshown in Figure 1. However, in this form of the invention these screwsare spaced a sufiicient distance apart to permit the reed 4 to vibratebetween them. In this arangement the motion of the reed causes a greaterdisturbance of the electrostatic field than is the case in themodifications in which the reed is positioned beneath the electrodes.

In the form of the invention shown in Figure 4, the reed i is positionedbeneath the condenser ill in the manner shown in Figures 1 and 2.However, in this modification, the condenser it consists of a sleeve 83and a pin 93, which is concentrically mounted therein and is insulatedfrom the sleeve by a lining M. The sleeve 8B is adjustably mounted inthe insulating cover 1. This form of the condenser is more compact thanthose previously discussed but may be easily and inexpensively made,

In all of the above described modifications of the invention, the reedis in close proximity to the exposed plates of the condenser 10 and,therefore, the vibration of the reed will disturb the capacity of thecondenser causing the vibrations, in the form of electricaloscillations, to be impressed upon the amplifying circuit. Thisadvantage is effected without connecting the reed to an electricalcircuit or to the ground.

Furthermore, it will be appreciated that changes can be made in the formof the reed and the condenser structure and in the electrical circuitwithout departin from the spirit of the invention.

I claim:

1. A unit for a musical instrument for translating mechanical vibrationsinto electrical oscillations, comprising stationary electrodes mutuallyforming an electrical capacity, an electrical circuit including saidcapacity and including means for charging the capacity, a vibratory reedfree of conductive connection with said circuit and positioned withrespect to said electrodes to vibrate within the electrostatic field ofsaid capacity, and means for vibrating said reed.

2. A unit for a musical instrument for translating mechanical vibrationsinto electrical oscillations comprising stationary electrodes mutuallyforming an electrical capacity, an electrical circuit including saidcapacity and including means for chargin the capacity, a vibratory reedfree of conductive connection with said circuit and positioned withrespect to said electrodes to vibrate within the electrostatic field ofsaid capacity, and pneumatic means for vibrating said reed.

3. A unit for a musical instrument for translating mechanical vibrationsinto electrical 0scillations, comprising stationary electrodes mutuallyforming an electrical capacity, an electrical circuit including saidcapacity and including means for charging the capacity, a metallicvibratory reed free of conductive connection with said circuit andpositioned with respect to said electrodes to vibrate Within theelectrostatic field of said capacity to set up electrical oscillations,pneumatic means for vibrating said reed, and said circuit also includingmeans for amplifying the said electric oscillations.

4. A unit for a musical instrument for translating mechanical vibrationsinto electrical oscillations comprising a pair of stationary electrodesmutually forming an electrical capacity, an electrical circuit includingsaid capacity and including means for charging the capacity, a metallicvibratory reed free of conductive connection with said circuit andpositioned with respect to said electrodes to vibrate within theelectrostatic field of said capacity to set up electrical oscillations,means for vibrating said reed, and said circuit also including means foramplifying the said electric oscillations.

5. A unit for a musical instrument for translating mechanical vibrationsinto electrical oscillations comprising apair of stationary electrodesmutually forming an electrical capacity, an electrical circuit includingsaid capacity and including means for charging the capacity, a metallicvibratory reed free of conductive connection with said circuit andpositioned directly beneath the said electrodes to vibrate within theelectrostatic field of said capacity to set up electrical oscillations,means for vibrating said reed, and said circuit also including means foramplifying the said electric oscillations.

6. A unit for a musical instrument for translating mechanical vibrationsinto electrical oscillations comprising a pair of stationary electrodesmutually forming an electrical capacity, an electrical circuit includingsaid capacity and including means for charging the capacity, a metallicvibratory reed free of conductive connection with said circuit andpositioned between the said electrodes to vibrate Within the electrostatic field of said capacity to set up electrical oscillations, meansfor vibrating said reed, and said circuit also including means foramplifying the said electric oscillations.

7. A unit for a musical instrument for translating mechanical vibrationsinto electrical oscillations comprising a reed cell, an insulating coverfor said cell, a pair of electrodes extending through the cover, saidelectrodes forming an electric capacity, an electrical circuit includingsaid capacity and including means to charge the capacity, a metallicreed free of conductive connection with said circuit and mounted withinthe cell for vibratory motion and positioned to vibrate within theelectrostatic field of said capacity, and pneumatic means to vibrate thereed.

8. A unit for a musical instrument for translating mechanical vibrationsinto electrical oscillations comprising a reed cell, an insulating coverfor said cell, a pair of electrodes extending through the cover, saidelectrodes forming an electric capacity, said capacity and includingmeans to charge the capacity, a metallic reed free of conductiveconnection with said circuit and mounted within the cell for vibratorymotion and positioned to vibrate within the electrostatic field of saidcapacity, to set up electrical oscillations, pneumatic means to vibratethe reed, and said circuit also including means for amplifying the saidelectrical oscillations.

9. A unit for a musical instrument for translating mechanical vibrationsinto electrical oscillations comprising a reed cell, an insulating coverfor said cell, a pair of electrodes extending through the cover, saidelectrodes forming an electrical capacity, an electrical circuitincluding said capacity and including means to charge the capacity, ametallic reed free of conductive connection with said circuit andmounted Within the cell for vibratory motion and positioned directlybeneath the electrodes to vibrate within the electrostatic field of saidcapacity to set up electrical oscillations, pneumatic means to vibratethe reed, and said circuit also including means for amplifying the saidelectrical oscillations.

an electrical circuit including 10. A unit for a musical instrument fortranslating mechanical vibrations into electrical 0scillationscomprising a reed cell, an insulating cover for said cell, a pair ofelectrodes extending through the cover, said electrodes forming anelectrical capacity, an electrical circuit including said capacity andincluding means to charge the a metallic reed free of conductiveconnection with said circuit and mounted within the cell for vibratorymotion and positioned directly between the electrodes to vibrate withinthe electrostatic field of said capacity to set up electricaloscillations, pneumatic means to vibrate the reed, and said circuit alsoincluding means for amplifying the said electrical oscillations.

11. A unit for a musical instrument for translating mechanicalvibrations into electrical oscillations, comprising a reed cell, aninsulating cover for said cell, a sleeve extending through said cover, apin concentrically mounted in the sleeve, an insulating means separatingthe sleeve and pin to form an electrical capacity, an electrical circuitincluding said capacity and including means to charge the capacity, ametallic reed free of conductive connection With said circuit andmounted within the cell for vibratory motion and positioned directlybeneath the electrodes to vibrate within the electrostatic field of saidcapacity to set up electrical oscillations, pneumatic means to vibratethe reed, and said circuit also including means for amplifying the saidelectrical oscillations.

12. In a musical instrument, a plurality of reeds chromatically arrangedin a musical scale, a pair of stationary electrodes adjacent each reed,each set of electrodes mutually forming an electrical capacity,electrical circuit means including the capacities and including meansfor charging the capacities, said reeds being free of conductiveconnection with said circuit and positioned with respect to saidelectrodes to vibrate within the electrostatic fields of saidcapacities, and means for vibrating the said reeds.

BURTON MINSHAIL.

REFERENCES CITED The following references are of record in the file orthis patent:

UNITED STATES PATENTS Number Name Date 1,953,753 Firestone Apr. 3, 19342,015,014 Hoschke Sept. 17, 1935 2,113,347 -IIoschke Apr. 5, 19382,246,855 Miessner June 24, 1941 2,257,830 Wolff et al. Oct. 7, 1941

